July 15, 2013

Allergic inflammation: focus on eosinophils



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Allergic inflammation: focus on eosinophils

  1. Hans-Uwe Simon
Article first published online: 15 JUL 2013
DOI: 10.1111/all.12231
Allergy

Allergy

Volume 68Issue 7pages 823–824July 2013



In allergic diseases, such as atopic dermatitis [1], bronchial asthma [2, 3], rhinosinusitis [4], or eosinophilic esophagitis [5], eosinophil numbers are usually increased. Therefore, the physiological and pathological roles of eosinophils remain a hot research topic. Recent progress in the understanding of eosinophil biology includes recognizing the capacity of eosinophils to generate different functional subsets under in vivo inflammatory conditions [6], as well as extracellular DNA-containing structures able to bind and kill bacteria [7, 8]. Furthermore, new pathogenetic insights reveal a molecular link between organismal metabolism and eosinophilic inflammation [9].
The molecular interactions between mast cells and eosinophils in allergic inflammatory responses have evoked an increasing research interest [10, 11]. The activation of eosinophils may result in tissue damage; therefore, inhibition of eosinophil effector functions is an important therapeutic strategy in eosinophilic disorders [12]. Interestingly, CRTH2 antagonists have been demonstrated to exhibit anti-eosinophilic activities in allergic rhinitis [13] and eosinophilic esophagitis [14]. But how can the anti-eosinophilic activity of a given drug be monitored? The results of a recent study suggest that, although reduced blood eosinophil numbers may reflect an anti-eosinophilic efficacy, they do not necessarily indicate a reduced eosinophilic inflammation [15]. Thus, the search for and testing of eosinophil biomarkers remain subjects of intense investigation [16].
In this issue of Allergy, several original articles report interesting new findings with implications for the diagnosis and treatment of eosinophilic diseases. Simon et al. demonstrate that adult patients suffering from eosinophilic esophagitis are frequently sensitized towardCandida albicans [17]. It is possible that such patients would benefit from antimycotic therapy. Muniz-Junqueira et al. describe morphological changes in eosinophils that correlate with the severity of asthma exacerbations in children [18]. Ueki et al. observed that retinoic acids increase the functional expression of eotaxin receptors, suggesting that vitamin A derivatives could play an important role in the tissue accumulation of eosinophils [19]. Moreover, the molecular events of the eotaxin receptor-mediated signaling pathway have been investigated by Shamri et al., and the reported data are likely relevant for both host defense and immunopathology [20]. Gleich et al. reviewed the current opinion with respect to the consequences of eosinophil-depleting treatments [21], and the data collected appear to be of great interest, particularly, because several anti-eosinophilic therapies are still in development.
Taken together, research in the field of eosinophilic diseases continues to be promising. Indeed, several new therapeutic approaches to different allergic conditions have also recently been reported in the Journal [22-24]. In spite of this progress, the role of the eosinophil in physiology and disease remains a subject for further research.

Acknowledgement

Work in the laboratory of HUS is supported by the Swiss National Science Foundation and Allergie-Stiftung Ulrich Müller-Gierok, Bern, Switzerland.

Conflict of interest

The author declares no conflict of interest.

References

  • 1
    Novak NSimon DAtopic dermatitis – from new pathophysiologic insights to individualized therapyAllergy 2011;66:830839.
  • 2
    Hoskins ARoberts JL IIMilne GChoi LDworski RNatural-source d-a-tocopheryl acetate inhibits oxidant stress and modulates atopic asthma in humans in vivoAllergy 2012;67:676682.
  • 3
    Agache IAkdis CJutel MVirchow JCUntangling asthma phenotypes and endotypesAllergy 2012;67:835846.
  • 4
    Pezato RSwierczynska-Krepa MNizankowska-Mogilnicka EDerycke LBachert CPérez-Novo CARole of imbalance of eicosanoid pathways and staphylococcal superantigens in chronic rhinosinusitisAllergy 2012;67:13471356.
  • 5
    Straumann AAceves SSBlanchard CCollins MHFuruta GTHirano I et al. Pediatric and adult eosinophilic esophagitis: similarities and differencesAllergy 2012;67:477490.
  • 6
    Roth NStädtler SLemann MHösli SSimon HUSimon DDistinct eosinophil cytokine expression patterns in skin diseases – the possible existence of functionally different eosinophil subpopulationsAllergy 2011;66:14771486.
  • 7
    Morshed MYousefi SStöckle CSimon HUSimon DThymic stromal lymphopoietin stimulates the formation of eosinophil extracellular trapsAllergy 2012;67:11271137.
  • 8
    Simon DSimon HUYousefi SExtracellular DNA traps in allergic, infectious, and autoimmune diseasesAllergy2013;68:409416.
  • 9
    Dietze JBöcking CHeverhagen JTVoelker MNRenz HObesity lowers the threshold of allergic sensitization and augments airway eosinophilia in a mouse model of asthmaAllergy 2012;67:15191529.
  • 10
    Elishmereni MAlenius HTBradding PMizrahi SShikotra AMinai-Fleminger Y et al. Physical interactions between mast cells and eosinophils: a novel mechanism enhancing eosinophil survival in vitroAllergy 2011;66:376385.
  • 11
    Elishmereni MBachelet INissim Ben Efraim AHMankuta DLevi-Schaffer FInteracting mast cells and eosinophils acquire an enhanced activation state in vitroAllergy 2013;68:171179.
  • 12
    Nissim Ben Efraim AHKarra LBen-Zimra MLevi-Schaffer FThe inhibitory receptor CD300a is up-regulated by hypoxia and GM-CSF in human peripheral blood eosinophilsAllergy 2013;68:397401.
  • 13
    Horak FZieglmayer PZieglmayer RLemell PCollins LPHunter MG et al. The CRTH2 antagonist OC000459 reduces nasal and ocular symptoms in allergic subjects exposed to grass pollen, a randomised, placebo-controlled, double-blind trialAllergy2012;67:15721579.
  • 14
    Straumann AHoesli SBussmann ChStuck MPerkins MCollins LP et al. Anti-eosinophil activity and clinical efficacy of the CRTH2 antagonist OC000459 in eosinophilic esophagitisAllergy 2013;68:375385.
  • 15
    Ullmann NBossley CJFleming LSilvestri MBush ASaglani SBlood eosinophil counts rarely reflect airway eosinophilia in children with severe asthmaAllergy 2013;68:402406.
  • 16
    Khoury PZagallo PTalar-Williams CSantos CSDinerman EHolland NC et al. Serum biomarkers are similar in Churg-Strauss syndrome and hypereosinophilic syndromeAllergy 2012;67:11491156.
  • 17
    Simon DStraumann ADahinden CSimon H-UFrequent sensitization to Candida albicans and profilins in adult eosinophilic esophagitisAllergy 2013;68:945948.
  • 18
    Muniz-Junqueira MIBarbosa-Marques SMJunqueira LF JrMorphological changes in eosinophils are reliable markers of the severity of an acute asthma exacerbation in childrenAllergy 2013;68:911920.
  • 19
    Ueki SNishikawa JYamauchi YKonno YTamaki MItoga M et al. Retinoid acids up-regulate functional eosinophil-driving receptor CCR3Allergy 2013;68:953956.
  • 20
    Shamri RYoung KMWeller PFPI3K, ERK, p38 MAPK and integrins regulate CCR-mediated secretion of mouse and human eosinophil-associated RNasesAllergy 2013;68:880889.
  • 21
    Gleich GJKlion ADLee JJWeller PFThe consequences of not having eosinophilsAllergy 2013;68:829835.
  • 22
    Sharma SKAlmeida FAKierstein SHortobagyi LLin TLarkin A et al. Systemic FasL neutralization increases eosinophilic inflammation in a mouse model of asthmaAllergy 2012;67:328335.
  • 23
    Lieberman JAMorotti RAKonstantinou GNYershov OChehade MDietary therapy can reverse esophageal subepithelial fibrosis in patients with eosinophilic esophagitis: a historical cohortAllergy 2012;67:12991307.
  • 24
    Sandell JHedman JSaarinen KHaahtela TSalt chamber treatment is ineffective in treating eosinophilic inflammation in asthma.Allergy 2013;68:125127.

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